Oil burner



.1. RENNER OIL BURNER Aug. 4, 1964 2 Sheets-Sheet 1 Filed June 13. 1960 INVENTOQ J. RENNER Aug. 4, 1964 OIL BURNER 2 Sheets-Sheet 2 Filed June 13, 1960 I-NVE NTOR .Ben zze1 6F2NEY5 ATT United States Patent 3,143,163 GHJ BURNER Josef Renner, Wiesenstrasse 54, Memmingerberg, near Memmingen, Bavaria, Germany Filed June 13, 1960, Ser. No. 35,525 Claims priority, application Germany Sept. 7, 1959 3 Ciaims. (Cl. 158-363) The present invention relates to improvements in oil burners and more particularly in an oil burner of the type which is provided with an oil pump and an atomizing nozzle, and an oil conduit connecting the pump to the nozzle.

If an oil burner of a conventional type is started a certain amount of oil will first escape from the mouth of the nozzle without being atomized and thus also without being ignited. This is due to the fact that for atomizing the oil a certain amount of pressure is required which, however, is not attained immediately when the burner is started, but only after the oil pump has run for a short length of time.

Although if such a burner is switched off, the pressure produced by the pump will quickly decrease, the remaining pressure will cause a certain amount of oil to emerge from the mouth of the nozzle and to be sprayed therefrom at an increasingly smaller arc and finally to drip therefrom.

This spilled and uncombusted oil forms a source of danger and also causes breakdowns in the operation of the burner.

It is an object of the present invention to provide a device which insures that even the first drop of oil which emerges from the mouth of the nozzle will be under such a pressure that it will be properly atomized and thus surely ignited.

Another object of the invention is to provide a device which insures that, when the burner is switched off, the discharge of oil from the mouth of the nozzle will he suddenly interrupted.

A further object of the invention consists in providing a device of the mentioned kind which is of a very simple construction and is very eficient and reliable in its operation without ever requiring any service.

Still another object of the invention is to design such a device in a manner so as to permit it to be installed in an oil burner of a conventional type or one which is already in use.

The device according to the invention is to be used in combination with an oil burner which is provided with an oil pump, an atomizing nozzle, and a conduit for connecting the oil pump to the nozzle, and it consists specifically of a control valve which is installed in the oil conduit closely adjacent to the mouth of the atomizing nozzle. This valve is provided with a movable valve member which in the closed position of the valve completely interrupts the flow of oil from the oil pump to the mouth of the nozzle, and in the open position of the valve allows the oil to flow to the mouth of the nozzle. This valve member is acted upon by a spring which tends to maintain it in the closed position. The valve is further designed in such a manner that the oil pressure in the oil conduit leading from the oil pump to the valve will act upon the valve member and move the same to the open position. An essential feature of the invention for attaining the above-mentioned objects consists in the fact that the spring has an initial tension of such a strength that the valve member will not be moved to the open position unless the pressure in the oil conduit leading from the oil pump to the valve corresponds at least to the pressure required for properly atomizing the oil which is ejected from the mouth of the nozzle.

These and other objects, features, and advantages of 3,143,163 Patented Aug. 4, 1964 the present invention will become further apparent from the following detailed description thereof, particularly when the same is read with reference to the accompanying drawings, in which- FIGURE 1 shows a diagrammatic cross section of a boiler which is provided with an oil burner and a nozzle head;

FIGURE 2 shows an enlarged longitudinal section of the nozzle head according to FIGURE 1;

FIGURE 3 shows a longitudinal section of a valve according to the invention in the closed position;

FIGURE 4 shows a view similar to FIGURE 3 but with the valve in the open position FIGURE 5 shows a top view of the valve according to FIGURES 3 and 4;

FIGURE 6 shows a longitudinal section of a valve according to a modification of the invention in the closed position;

FIGURE 7 shows a view similar to FIGURE 6 but with the valve in the open position;

FIGURE 8 shows a view, partly in section and partly in a side view, of a valve according to a further modification of the invention in the closed position;

FIGURE 9 shows a longitudinal section of the valve according to FIGURE 8, but in the open position; while FIGURE 10 shows a cross section taken along line XX of FIGURE 9.

As illustrated in FIGURE 1, the boiler 1 is provided with an oil burner which essentially consists of an oil pump 2, a blower 3, a pipe line 4, and an atomizing nozzle 5. Oil pump 2 is driven in the usual manner by an electric motor, not shown, to pump the oil through pipe 4 to nozzle 5 so that it will then be ejected from the mouth 6 of the nozzle in the form of an atomized oil jet 7 which is then ignited by the electrodes 8. The combustion gases pass through boiler 1 in the direction as indicated in FIGURE 1 by the arrows 9.

The atomizing nozzle 5 is screwed into a nozzle head or housing 10 which, in turn, is connected to pipe line 4. This nozzle head 10 together with the atomizing nozzle 5 is illustrated in an enlarged cross section in FIGURE 2.

The nozzle head 10 contains a chamber 11 through which the oil passes in the direction as indicated by the arrows 13. Nozzle head It) is screwed upon the end of pipe line 4 and contains at its other end the atomizing nozzle 5. The oil flows from pipe 4 through chamber 11, then through the cylindrical filter 12 to the inside of the filter and then through the mouth 6 of nozzle 5.

The atomizing nozzle 5 is connected by outer screw threads 14 to nozzle head 10 and it also has inner screw threads 15 into which the outer screw threads 16 on one end 18 of a tubular valve housing 17 are screwed which thus communicates with bore 19 in the atomizing nozzle which terminates into the nozzle mouth 6.

Valve housing 17 contains a valve member 20 which consists of a pistonlike part 21 and an enlarged cylindrical part 22. The pistonlike part 21 has a screw 23 screwed therein which is associated with a coil spring 24 which acts upon valve member 20 to press its conical surface 25 against a corresponding conical surface 26 in valve housing 17.

Between the conical surface 25 and the open end 18 the valve housing 17 is further provided with radial bores 28 which in the closed position of the valve are covered by the enlarged part 22. The wall portion of valve member 20 intermediate the pistonlike part 21 and the enlarged part 22 is also provided with bores 29.

When the valve is in the open position, as illustrated in FIGURE 4, the oil can flow from chamber 11 through the filter member 12 and bores 23 into a chamber 30 which is formed between valve housing 17 and valve member 20. From this chamber 30 the oil then flows through bores 29 into chamber 22 and from chambers 22' to the open end 18 of the valve housing and then to the nozzle opening 6.

The pistonlike part 21 of valve member 2% is surrounded by a recessed neck portion 31 which encloses the spring 24.

When the oil pump 2 is switched off, the valve will be in the position as illustrated in FIGURE 3. Oil pump 4 and chamber 11 of nozzle head are then filled with oil. The head of screw 23 fits loosely into the neck portion 31 and is provided with recesses 53, as shown in FIGURE 5, through which the annular chamber 32 containing spring 24 also communicates with chamber 11. Valve member 263 then closes valve housing 17 tightly by engaging with its surface 25 against the surface 26.

If oil pump 2 is started, the pressure increases at the inside of pipe line 4 and within chamber 11. In accordance with the cross-sectional area of the piston-like part 21 of valve member 20, this pressure also acts upon the latter. However, since spring 24 has a certain initial tension, valve member 2% will at first be held in the closed position until at a certain pressure, which is determined by the initial tension of spring 24 and at least corresponds to the pressure which is required to attain a proper atomizing of the oil at the nozzle mouth 6, valve member will move from the closed position as shown in FIGURE 3 to the opened position as shown in FIGURE 4, in which the head of screw 23 engages with the shoulder 33 in the annular chamber 32. Since the pressure in bore 19 is slightly lower than that in chamber 3%) and also lower than the pressure in chamber 11, valve member 20 will be securely retained in the open position.

The change from the closed position of the valve, as shown in FIGURE 3, to the open position, as shown in FIGURE 4, occurs very suddenly. At this movement, valve member 22 compresses the oil in bore 1% rapidly so that the oil pressure will suddenly increase therein with the result that the oil will be immediately atomized at the nozzle mouth 6. It will thus be absolutely prevented that small amounts of oil will flow out of the nozzle mouth 6 under a low pressure and drip off without being atomized.

When pump 2 is switched oif, resulting in a decrease in pressure at the inside of pipeline 4 and chamber 11, valve member 29 will be moved from the open to the closed position in accordance with the pressure determined by the initial tension of spring 24. Such a movement results in creating a suction effect of oil in bore 19 so that the drops of oil which are then near the nozzle opening 6 will be sucked back and will therefore not drip off the nozzle opening without being atomized.

FIGURES 6 and 7 illustrate a slightly modified embodiment of the invention. Underneath the cylindrical filter member 12, the body of valve housing 37 is provided with an annular chamber 34 and bores 35 leading from this chamber to the conical surface 36 on the inner wall of valve housing 37. Valve member 20' also contains bores 33 leading from a central recess in the enlarged cylindrical part of this member to the outer conical surface 39. The inner ends of bores 35 in the conical surface 36 of the valve housing are staggered relative to the outer ends of bores 38 in the corresponding conical surface 39 of valve member 263'. When the valve is in the closed position, as illustrated in FIGURE 6, the conical surfaces 36 and 39 engage with each other under the pressure of spring 24 and thus close bores 38 and 35 tightly.

The valve according to FIGURES 6 and 7 has the advantage that, when the pressure in the main chamber 1 in nozzle head It? is sufficient to overcome the initial tension of spring 24', the oil can flow immediately into chamber 3% between valve member 2%? and its housing 37 so that the effective cross-sectional area of the valve member will be considerably increased and the movement of the valve member from the closed position according to FIGURE 6 to the open position according to FIGURE 7, that is, in the direction as shown by the arrow in FIG- URE 6, will be considerably accelerated. Such a quick movement of the valve member has the advantages that the length of time which is required until the full pressure of the oil becomes effective within chamber 19, as shown in FIGURE 2, will be reduced and that the compression within chamber 19 will occur more suddenly.

FIGURES 8 to 10 illustrate still another modified embodiment of the invention in which the valve member &0 slides along the valve housing 41. Valve member 45) is of a cylindrical pot-shape and carries the filter member 42. Valve housing M has integrally therewith a central stud 4-3 which extends through the bottom 44 of valve member 40 and has in its end a screw 45, the head of which extends over the bottom id and serves as a stop member to limit the movement of valve member 49 relative to valve housing 41. The biased valve spring 46 normally maintains valve member 40 in the closed position. The chamber or recess 47 containing spring 46 communicates through bores 43 with the main bore 49 in valve housing 41 which after the valve has been inserted into nozzle head 10, connects with chamber 19, as shown in FIGURE 2. The outer wall 52 of valve member 40 is provided with apertures 5 as indicated in FIGURE 10, and the outer wall of valve housing 41 is provided with apertures 51;. The cylindrical wall 52 is in sealing engagement with the inner peripheral surface of valve housing 41 and the bottom 44 of valve member 40 is likewise in sealing engagement with stud 43.

As illustrated in FIGURE 8, a coil spring 46' may also be provided around the outer part of valve housing 41 either in place of or in addition to spring 46.

When the oil burner is switched off, valve member 4% is in the position as shown in FIGURE 8. If the oil pressure in the main chamber 11 in nozzle head 10 increases, it acts upon the bottom 44 and shifts valve member 40 with filter member 24 against the action of spring 46 and 46 from the position according to FIG- URE 8 to the position according to FIGURE 9. Apertures 5t) and 51 will then be substantially in alignment with each other so that the oil can flow into the main bore 49. At this movement, the oil in chamber 47 will be compressed and this pressure will be transmitted through bores 48 to the main bore 49 and then to chamber 1?, as shown in FIGURE 2.

Although my invention has been illustrated and described with reference to the preferred embodiments thereof, I wish to have it understood that it is in no way limited to the details of such embodiments, but is capable of numerous modifications within the scope of the appended claims.

Having thus fully disclosed my invention, what I claim is:

1. In an oil burner having an oil pump, an atomizing nozzle having a hollow nozzl housing and a nozzle mouth at one end, a conduit connecting said pump to the other end of said nozzle housing, a valve mounted within said nozzle housing with an annular space therebetween and screwed into said nozzle housing, said valve having a hollow valve housing and a movable valve member mounted therein, a cylindrical filter member surrounding said valve housing, said movable valve being slidable in said valve housing toward and away from said nozzle mouth to open and close fluid communication from said conduit and said nozzle month, said movable valve having a central reduced shaft portion, said valve housing having a central inner collar portion surrounding said shaft for slidably guiding said movable valve, a screw having an enlarged head of greater diameter than said reduced shaft portion threaded into the end of said shaft adjacent the conduit end of the nozzle housing, said valve housing having an annular space between said collar and said screw head, a spring mounted in said annular space between said collar and screw head to bias said movable valve member toward said conduit end of said nozzle housing, said annular space being provided with an enlarged portion receiving said screw head, said shaft having an enlarged shoulder portion at its end adjacent the nozzle mouth, with a skirt portion depending from said shoulder portion, said valve housing having apertures providing communication between said filter and said movable valve, said shoulder of said movable valve having apertures communicating with said nozzle mouth whereby when oil under pressure passes into said nozzle housing the pressure against said screw head will force said movable valve toward said nozzle mouth and move said apertures of said shoulder of said movable valve into communication with the apertures in said valve housing, whereby oil under pressure may flow from said conduit through said nozzle mouth via said filter member and valve housing and movable valve apertures.

2. An atomizing nozzle according to claim 1, wherein 6 said collar of said valve housing is formed integrally with the housing, and wherein said shoulder and skirt portion and central shaft portion are formed integrally with one another.

3. An atomizing nozzle according to claim 1, wherein said shoulder portion is tapered.

References Cited in the file of this patent UNITED STATES PATENTS 1,858,302 Marshall May 17, 1932 2,294,029 High Aug. 25, 1942 2,621,077 Pieroni Dec. 9, 1952 2,644,481 Perlman July 7, 1953 2,665,167 High Jan. 5, 1954 2,893,647 Wortman July 7, 1959 FOREIGN PATENTS 499,937 Germany June 14, 1930 294,457 Switzerland Jan. 16, 1954 

1. IN AN OIL BURNER HAVING AN OIL PUMP, AN ATOMIZING NOZZLE HAVING A HOLLOW NOZZLE HOUSING AND A NOZZLE MOUTH AT ONE END, A CONDUIT CONNECTING SAID PUMP TO THE OTHER END OF SAID NOZZLE HOUSING, A VALVE MOUNTED WITHIN SAID NOZZLE HOUSING WITH AN ANNULAR SPACE THEREBETWEEN AND SCREWED INTO SAID NOZZLE HOUSING, SAID VALVE HAVING A HOLLOW VALVE HOUSING AND A MOVABLE VALVE MEMBER MOUNTED THEREIN, A CYLINDRICAL FILTER MEMBER SURROUNDING SAID VALVE HOUSING, SAID MOVABLE VALVE BEING SLIDABLE IN SAID VALVE HOUSING TOWARD AND AWAY FROM SAID NOZZLE MOUTH TO OPEN AND CLOSE FLUID COMMUNICATION FROM SAID CONDUIT AND SAID NOZZLE MOUTH, SAID MOVABLE VALVE HAVING A CENTRAL REDUCED SHAFT PORTION, SAID VALVE HOUSING HAVING A CENTRAL INNER COLLAR PORTION SURROUNDING SAID SHAFT FOR SLIDABLY GUIDING SAID MOVABLE VALVE, A SCREW HAVING AN ENLARGED HEAD OF GREATER DIAMETER THAN SAID REDUCED SHAFT PORTION THREADED INTO THE END OF SAID SHAFT ADJACENT THE CONDUIT END OF THE NOZZLE HOUSING, SAID VALVE HOUSING HAVING AN ANNULAR SPACE BETWEEN SAID COLLAR AND SAID SCREW HEAD, A SPRING MOUNTED IN SAID ANNULAR SPACE BETWEEN SAID COLLAR AND SCREW HEAD TO BIAS SAID MOVABLE VALVE MEMBER TOWARD SAID CONDUIT END OF SAID NOZZLE HOUSING, SAID ANNULAR SPACE BEING PROVIDED WITH AN ENLARGED PORTION RECEIVING SAID SCREW HEAD, SAID SHAFT HAVING AN ENLARGED SHOULDER PORTION AT ITS END ADJACENT THE NOZZLE MOUTH, WITH A SKIRT PORTION DEPENDING FROM SAID SHOULDER PORTION, SAID VALVE HOUSING HAVING APERTURES PROVIDING COMMUNICATION BETWEEN SAID FILTER AND SAID MOVABLE VALVE, SAID SHOULDER OF SAID MOVABLE VALVE HAVING APERTURES COMMUNICATION WITH SAID NOZZLE MOUTH WHEREBY WHEN OIL UNDER PRESSURE PASSES INTO SAID NOZZLE HOUSING THE PRESSURE AGAINST SAID SCREW HEAD WILL FORCE SAID MOVABLE VALVE TOWARD SAID NOZZLE MOUTH AND MOVE SAID APERTURES OF SAID SHOULDER OF SAID MOVABLE VALVE INTO COMMUNICATION WITH THE APERTURES IN SAID VALVE HOUSING, WHEREBY OIL UNDER PRESSURE MAY FLOW FROM SAID CONDUIT THROUGH SAID NOZZLE MOUTH VIA SAID FILTER MEMBER AND VALVE HOUSING AND MOVABLE VALVE APERTURES. 